MIMO Reconfigurable Antennas for Wi-Fi 2.4 GHz Communication.

Abstract

We are living in the era of wireless communication. From accessing Internet through smartphones and Wi-Fi, changing TV channels with remote controls, using wireless computer peripherals like mouse, keyboards and headphones to mobile body area networks for keeping track of heart rate, blood pressure and body temperature, applications of wireless communication is everywhere. The most frequent and common use of wireless communication is mobile phones or cellular phones which uses the radio waves to carry data from one place to another. Though there are many advantages of wireless communication which makes it so popular, there are two most significant challenges in implementing a wireless communication system: multipath propagation and limited information rate. The concept of multipath propagation refers to travelling of wireless signal to the receiving antenna via different paths in space resulting in inter-symbol interference and fading. This phenomenon leads to failure of maximum use of the bandwidth resulting in low information rate. The problematic event of multipath propagation can be exploited by using more than one antenna (MIMO) in the sending and the receiving side. Multiple sending antennas use the concept of space diversity by sending same data signal through different path based on the fact that different version of the same signal will be received by the receiver increasing quality and reliability of the received data signal.Though in the current usage scenario, MIMO actually exploits multipath propagation concept for carrying more than one data stream over the same radio signal. One of the most important factors that influence the efficiency of MIMO antenna systems is the design layout of multiple antennas. Microstrip antennas, having small height and width, low cost, low weight and small volume can be a suitable candidate for being used as MIMO. The wireless performance of locally limited wireless communication systems such as Bluetooth and Wi-Fi using 2.4 GHz unlicensed band can be increased significantly by incorporating the advantages of MIMO and microstrip antenna technology. In this paper, the performance of MIMO Microstrip antenna using OFDM technique for 2.4 GHz communication has been evaluated.